Long term objective of this project is to understand changes in glycoconjugates and their interactions with lectin receptors in rheumatoid, and other diseases. Rheumatoid diseases are known to be associated with changes in oligosaccharide structures, but very little is know about effects of these changes on the interaction between glycoconjugates and their lectin receptors. One of the main problems is the lack of adequate methods for the analysis of lectin activity in complex biological samples, and we shall focus significant efforts to development and improvement of these methods. A novel set of compounds, named glycoprobes, will be used to identify and purify lectins that bind to specific, carbohydrate structures. Individual lectins will be characterized by MALDI-MS, and their identity determined by peptide mapping. We hope that the information about changes in the activity of lectins in rheumatoid diseases will, in the long run, help identify future targets for more specific therapy of rheumatoid diseases.